package cobra
import (
"bytes"
"fmt"
"io"
"os"
"strings"
)
// GenZshCompletionFile generates zsh completion file.
func (c *Command) GenZshCompletionFile(filename string) error {
outFile, err := os.Create(filename)
if err != nil {
return err
}
defer outFile.Close()
return c.GenZshCompletion(outFile)
}
// GenZshCompletion generates a zsh completion file and writes to the passed writer.
func (c *Command) GenZshCompletion(w io.Writer) error {
buf := new(bytes.Buffer)
writeHeader(buf, c)
maxDepth := maxDepth(c)
writeLevelMapping(buf, maxDepth)
writeLevelCases(buf, maxDepth, c)
_, err := buf.WriteTo(w)
return err
}
func writeHeader(w io.Writer, cmd *Command) {
fmt.Fprintf(w, "#compdef %s\n\n", cmd.Name())
}
func maxDepth(c *Command) int {
if len(c.Commands()) == 0 {
return 0
}
maxDepthSub := 0
for _, s := range c.Commands() {
subDepth := maxDepth(s)
if subDepth > maxDepthSub {
maxDepthSub = subDepth
}
}
return 1 + maxDepthSub
}
func writeLevelMapping(w io.Writer, numLevels int) {
fmt.Fprintln(w, `_arguments \`)
for i := 1; i <= numLevels; i++ {
fmt.Fprintf(w, ` '%d: :->level%d' \`, i, i)
fmt.Fprintln(w)
}
fmt.Fprintf(w, ` '%d: :%s'`, numLevels+1, "_files")
fmt.Fprintln(w)
}
func writeLevelCases(w io.Writer, maxDepth int, root *Command) {
fmt.Fprintln(w, "case $state in")
defer fmt.Fprintln(w, "esac")
for i := 1; i <= maxDepth; i++ {
fmt.Fprintf(w, " level%d)\n", i)
writeLevel(w, root, i)
fmt.Fprintln(w, " ;;")
}
fmt.Fprintln(w, " *)")
fmt.Fprintln(w, " _arguments '*: :_files'")
fmt.Fprintln(w, " ;;")
}
func writeLevel(w io.Writer, root *Command, i int) {
fmt.Fprintf(w, " case $words[%d] in\n", i)
defer fmt.Fprintln(w, " esac")
commands := filterByLevel(root, i)
byParent := groupByParent(commands)
for p, c := range byParent {
names := names(c)
fmt.Fprintf(w, " %s)\n", p)
fmt.Fprintf(w, " _arguments '%d: :(%s)'\n", i, strings.Join(names, " "))
fmt.Fprintln(w, " ;;")
}
fmt.Fprintln(w, " *)")
fmt.Fprintln(w, " _arguments '*: :_files'")
fmt.Fprintln(w, " ;;")
}
func filterByLevel(c *Command, l int) []*Command {
cs := make([]*Command, 0)
if l == 0 {
cs = append(cs, c)
return cs
}
for _, s := range c.Commands() {
cs = append(cs, filterByLevel(s, l-1)...)
}
return cs
}
func groupByParent(commands []*Command) map[string][]*Command {
m := make(map[string][]*Command)
for _, c := range commands {
parent := c.Parent()
if parent == nil {
continue
}
m[parent.Name()] = append(m[parent.Name()], c)
}
return m
}
func names(commands []*Command) []string {
ns := make([]string, len(commands))
for i, c := range commands {
ns[i] = c.Name()
}
return ns
}
